The Olympic stadium site being prepared. 'What integrity is there within companies to profit from lucrative Olympics and infrastructure projects while using a secret list to deny decent people work?' Photograph: Tom Jenkins

I applied for a post with Ciba-Geigy at their UK headquarters in Manchester and following a rigorous interview I was offered the job. A few days later they phoned to say that they were withdrawing their offer because my name was on the Economic League's blacklist. At the time this job was an opportunity, when I was on a fairly low wage and with a young family, to move closer to my mother who was terminally ill.

What had I done wrong? I don't know. Was it because I'd been a Labour party member since the age of 15; was it because I was a trade unionist? Was it for being involved in supporting the miners strike? Or was it because I helped organise the national demonstrations of the anti-apartheid movement? These were all fairly mainstream activities at the time but someone, somewhere had determined that my name should be included on an arbitrary secret list that our major industries used as a benchmark to hire and fire people.

We are entitled to know who are the conspirators who compile these lists. Which companies used these lists? Why did they not inform their shareholders? When will they be prosecuted?

It is only because of the honesty and integrity of an embarrassed human resources person at Ciba-Geigy that I knew the real reason behind their decision. Someone had added my name to a McCarthyite list and yet I had no redress and it was only goodwill that led to me finding out. Imagine how many people have failed to get jobs and never realised why.

Now we have revelations of another Economic League-style blacklist of construction workers, which has been used by companies highly reliant on government contracts. What integrity is there within companies to profit from lucrative Olympics and infrastructure projects while using a secret list to deny decent people work?

We need an inquiry into this latest construction industry scandal. When a person's life has been affected by a secret blacklist they need to have access to this information and they should have rights to compensation. We will see, following the parliamentary debate today, whether this coalition is in fact in favour of freedom and individual liberties, because those that are will be counted alongside me in the voting lobbies.

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